Memory management problem \ VOGONS

Memory management problem

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First post, by Timbi

Posted on 2023-11-12, 23:38

Timbi Offline

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All three samples share same HDD image, I wish I could set the 86Box/PCem to make the memory management similar to how it is done in DOSBox X.

1Config.sys
2DEVICE=C:\WINDOWS\HIMEM.SYS
3DOS=HIGH,UMB
4DEVICEHIGH=C:\WINDOWS\EMM386.EXE RAM
5DEVICEHIGH=C:\WINDOWS\COMMAND\DRVSPACE.SYS /MOVE
6DEVICEHIGH=C:\WINDOWS\COMMAND\DISPLAY.SYS CON=(EGA,,1)
7COUNTRY=048,852,C:\WINDOWS\COMMAND\COUNTRY.SYS
8devicehigh=C:\WINDOWS\cwdinit.exe /A
9FILESHIGH=25
10LASTDRIVEHIGH=F
11BUFFERSHIGH=30
12STACKSHIGH=9,256
13FCBSHIGH=4
14
15Autoexec.bat
16@ECHO OFF
17PROMPT $P$G
18PATH=C:\;C:\NC;C:\WINDOWS;C:\WINDOWS\COMMAND
19SET BLASTER=A240 I9 D3 T4
20LH MODE CON CODEPAGE PREPARE=((852) C:\WINDOWS\COMMAND\EGA.CPI)
21LH MODE CON CODEPAGE SELECT=852
22LH KEYB PL,,C:\WINDOWS\COMMAND\KEYBRD4.SYS
23LH SMARTDRV.EXE C 1024 512
24LH MOUSE.COM
25LH NC.EXE

Testing done with command mem /c /p
config:
16MB of RAM
Pentium 1 90MHz
All the shadowing is off in BIOS in 86Box/PCem

In DOSBox X the high memory seems to be better managed, most of drivers is loaded to high as expected. I'm hoping I can configure the rest to work similar to this. Loading some games as Bumpy with insufficient lower memory results with heavy display artifacts. Even though I can run the game after unloading some of the drivers, I wonder if it is possible to keep it clean and nice as in DOSBox X.
I know I'm not using other tools to manage memory right now, but it seems the problem is in the settings I cannot figure out.

The language is not English but I'm sure it is intuitive enough.

Reply 1 of 5, by Timbi

Posted on 2023-11-13, 09:52

Timbi Offline

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I beg for help. Anyone? My post was very polite.

Reply 2 of 5, by Disruptor

Posted on 2023-11-13, 13:02

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Timbi wrote on 2023-11-13, 09:52:

I beg for help. Anyone? My post was very polite.

If you do not need EMS, try to replace "RAM" in CONFIG.SYS' EMM386 line with "NOEMS".
Try to create a boot menu for the configurations where you really need EMS.

And try to get rid of DRVSPACE. I'm sure you won't need it.

And, why do you have so few UMB?
It looks like 18 KB (+64 from EMS page frame).
Check for more usable upper memory areas with MSD.
Try to include them with I= settings.

Reply 3 of 5, by Gmlb256

Posted on 2023-11-13, 13:40

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86Box and PCem attempts to make a more accurate representation of computers than DOSBox (and DOSBox-X which is a fork). The emulated Socket 7 motherboard should normally have the region C800-EFFF available for UMB and the EMS page frame, provided that a period correct video card was selected.

As Disruptor said, try to include them with I= parameter in EMM386 and if you don't need EMS at all then add NOEMS as well to obtain more UMB.

Reply 4 of 5, by weedeewee

Posted on 2023-11-13, 16:19

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Timbi wrote on 2023-11-13, 09:52:

I beg for help. Anyone? My post was very polite.

After reading your post. I guess your question is, why is the amount of free memory so lacking in pcem and 86box? .

To which,
i guess,
the simplest answer would be
86box and pcem emulate a real computer, dosbox-x emulates an optimized dos environment.

Right to repair is fundamental. You own it, you're allowed to fix it.
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Reply 5 of 5, by Timbi

Posted on 2023-11-13, 19:49

Timbi Offline

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Thanks for your answers, I will try these techniques to see what can be done to give it shape.

Disruptor wrote on 2023-11-13, 13:02:

Try to create a boot menu for the configurations where you really need EMS.

Yes, it is good idea, but I have already menu with DOS CD, DOS [EMS] and WINDOWS. I will add NOEMS option soon.

weedeewee wrote:
why is the amount of free memory so lacking in pcem and 86box? .

From now on, I fixed the problem partially by changing machine type to Super Socket 7 with ASUS P5A. I'm guessing that its newer BIOS allows to have more memory.

I also changed mouse driver to newer version (also Microsoft) mouse.exe. mouse.com seemed to produce memory conflicts specifically for PCem and 86box, but not with DOSbox, I don't know why, but

dosbox-x emulates an optimized dos environment.

might be the answer here.

Here is how it been with the old mouse driver mouse.com
I couldn't load mouse.com driver together with mode codepage and keyb and ncmain. If I excluded one of these, the game worked fine and it seems like low bottom memory wasn't the case, but memory errors caused by the mouse driver (but it was fine in DOSBox with the same driver).
I have included picture how the game looked on VGA. With EGA it was black and red.

It is now solved and I hope this topic will help the other people, who will encounter same problem.

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